def aux_logits():
return mo.siso_sequential([
relu(),
avg_pool2d(D([5]), D([3]), D(['VALID'])),
conv2d(D([128]), D([1])),
batch_normalization(),
relu(),
global_convolution(D([768])),
batch_normalization(),
relu(),
flatten(),
fc_layer(D([10]))
])
def intermediate_node_fn(num_inputs, filters):
return mo.siso_sequential([
add(num_inputs),
conv2d(D([filters]), D([3])),
batch_normalization(),
relu()
])
def conv_op(filters, filter_size, stride, dilation_rate, spatial_separable):
if spatial_separable:
return mo.siso_sequential([
conv2d(D([filters]), D([[1, filter_size]]), D([[1, stride]])),
batch_normalization(),
relu(),
conv2d(D([filters]), D([[filter_size, 1]]), D([[stride, 1]])),
])
else:
return conv2d(D([filters]), D([filter_size]), D([stride]),
D([dilation_rate]))
def generate_search_space(num_nodes_per_cell, num_normal_cells,
num_reduction_cells, init_filters, stem_multiplier):
global global_vars, hp_sharer
global_vars = {}
hp_sharer = hp.HyperparameterSharer()
hp_sharer.register('drop_path_keep_prob',
lambda: D([.7], name='drop_path_keep_prob'))
stem_in, stem_out = stem(int(init_filters * stem_multiplier))
total_steps_in, total_steps_out = mo.identity()
global_vars['total_steps'] = total_steps_out['out']
normal_cell_fn = create_cell_generator(num_nodes_per_cell, False)
reduction_cell_fn = create_cell_generator(num_nodes_per_cell, True)
total_cells = num_normal_cells + num_reduction_cells
has_reduction = [False] * num_normal_cells
for i in range(num_reduction_cells):
has_reduction[int(
float(i + 1) / (num_reduction_cells + 1) *
num_normal_cells)] = True
inputs = [stem_out, stem_out]
filters = init_filters
aux_loss_idx = int(
float(num_reduction_cells) /
(num_reduction_cells + 1) * num_normal_cells) - 1
outs = {}
cells_created = 0.0
for i in range(num_normal_cells):
if has_reduction[i]:
filters *= 2
connect_new_cell(
reduction_cell_fn(filters, (cells_created + 1) / total_cells),
inputs)
cells_created += 1.0
connect_new_cell(
normal_cell_fn(filters, (cells_created + 1) / total_cells), inputs)
cells_created += 1.0
if i == aux_loss_idx:
aux_in, aux_out = aux_logits()
aux_in['in'].connect(inputs[-1]['out'])
outs['out0'] = aux_out['out']
_, final_out = mo.siso_sequential([(None, inputs[-1]),
relu(),
global_pool2d(),
dropout(D([1.0])),
fc_layer(D([10]))])
outs['out1'] = final_out['out']
return {'in0': stem_in['in'], 'in1': total_steps_in['in']}, outs
def generate_stage(stage_num, num_nodes, filters, filter_size):
h_connections = [
Bool(name='%d_in_%d_%d' % (stage_num, in_id, out_id))
for (in_id,
out_id) in itertools.combinations(range(1, num_nodes + 1), 2)
]
return genetic_stage(
lambda: mo.siso_sequential([
conv2d(D([filters]), D([filter_size])),
batch_normalization(),
relu()
]), lambda num_inputs: intermediate_node_fn(num_inputs, filters), lambda
num_inputs: intermediate_node_fn(num_inputs, filters), h_connections,
num_nodes)
def forward_fn(di, is_training=True):
inp = relu(di['in0']) if add_relu else di['in0']
if height == final_height and channels == final_channels:
out = inp
elif height == final_height:
out = conv(inp)
out = bn(out)
else:
path1 = avg_pool(inp)
path1 = conv1(path1)
path2 = slice_layer(pad(inp))
path2 = avg_pool(path2)
path2 = conv2(path2)
out = concat([path1, path2])
out = bn(out)
return {'out': out}
def wrap_relu_batch_norm(op):
return mo.siso_sequential([relu(), op, batch_normalization()])